Back to articles
AI/ML

AI-Powered Newsletter Systems

How we built AI Insider's personalized content delivery system using OpenAI. Architecture decisions for subscription-based content platforms.

December 15, 20259 min read

The AI Insider Vision

AI Insider aimed to solve information overload. Instead of users searching for AI news, we would curate and deliver personalized content based on their interests.

System Architecture

Content Pipeline

  • **Aggregation** - Collect articles from 50+ sources
  • **Processing** - Extract key information using NLP
  • **Categorization** - Classify content by topic
  • **Personalization** - Match content to user preferences
  • **Delivery** - Send via email at optimal times
  • The Role of OpenAI

    We used GPT for several tasks:

    Content Summarization

    def summarize_article(content: str) -> str:

    response = openai.ChatCompletion.create(

    model="gpt-3.5-turbo",

    messages=[

    {"role": "system", "content": "Summarize this article in 2-3 sentences."},

    {"role": "user", "content": content}

    ]

    )

    return response.choices[0].message.content

    Personalized Introductions

    Each newsletter had a personalized intro based on the user's reading history.

    Content Recommendations

    We combined collaborative filtering with GPT-based similarity scoring.

    Subscription Model

    Tiers

  • **Free**: Weekly digest, 5 articles
  • **Pro**: Daily digest, unlimited articles, book recommendations
  • **Premium**: Everything + courses, priority support
  • Implementation

    class Subscription(models.Model):

    user = models.OneToOneField(User, on_delete=models.CASCADE)

    tier = models.CharField(max_length=20, choices=TIER_CHOICES)

    features = models.JSONField(default=dict)

    def can_access(self, feature: str) -> bool:

    return feature in TIER_FEATURES[self.tier]

    Personalization Engine

    User Preferences

    We tracked:

  • Explicit preferences (topics selected during onboarding)
  • Implicit preferences (articles opened, time spent)
  • Feedback (thumbs up/down on recommendations)
  • Content Matching

    def score_content_for_user(user: User, content: Content) -> float:

    explicit_score = match_topics(user.preferences, content.topics)

    implicit_score = similarity_to_history(user.reading_history, content)

    recency_score = calculate_recency(content.published_at)

    return (

    0.4 * explicit_score +

    0.4 * implicit_score +

    0.2 * recency_score

    )

    Results

    After launch:

  • 500+ subscribers in first month
  • 45% open rate (industry average: 20%)
  • 12% click-through rate
  • Growing MRR
  • Challenges

    Cost Management

    OpenAI API calls add up. We implemented:

  • Caching for repeated queries
  • Batch processing during off-peak hours
  • Fallback to simpler models when appropriate
  • Quality Control

    AI-generated content needs human oversight:

  • Review queue for summaries
  • Feedback loop for improvements
  • Manual curation for premium content
  • Key Takeaways

  • **AI augments, doesn't replace** - Human curation is still valuable
  • **Start simple** - We launched with basic personalization, improved over time
  • **Monitor costs** - AI APIs can get expensive quickly
  • **Measure everything** - A/B test personalization approaches
  • Building AI Insider taught me that the best AI products feel magical but are built on solid engineering foundations.